Process of reducing ores



speciiication.

limieten-ted @et liiiii,

ormoni@ 'VMTER EWN WEI/ENT, El? liVl-LSENGTGN, DSTRCT OF COLUMBIA,ASSIGNO'R .TO y Tltllll GORRFLTION, OF WASHINGTON, DISTRICT Of COLUMBA,A 200Bv LELOC'ESS 0F REB'UCNG OR'ES.

financer-ion tiled October e, 1920. Serial No. 414,526.

To @ZZ whom t may concern:

Be it known that l, lflva'n'rnn E. Timur, citizen ci? the Unite-dvStates ct America, residingat lllashington, in the District of Columbia,have invented certain new and useful improvements in Processes oi.'Reducing- Gres, ott which the following 1s a The present inventionrelatee to a process of reducing iron and other metallic ores to metal.

lt is the object oi the invention to provide a process tor reducing ironores to metal by employing a. iuei such as coal and effecting a recoveryof the byproducts of the coal employed in reducing the iron. v

lt is a further object of the invention to provide a process ci?reducing iron and like metals at temperatures sufliciently high toreduce the iron, lout at temperaturesbelow that which causes sintering,"fusing, agglomerating or slagging formation1 lt' is a still furtherobiect ot the invention to provide a process for reducingsy iron andlike metalsbjT using coals and lignites from which the volatile contenthas been eX- pelled.

It is also an object ci the invention to l remove impurities from theiron ore and been found from the coai before the final im-zltingI of theiron takes piace. lnother words, the slag forming' materials areeliminated in advance of the actual `iinal melting ot the metal.

to recover the lay-products under conditions that give 'the maximumyields ci oils. lt has been found tl'iat-when coal is suiciently finelyground' a maximum yield of oil can be obtained from tlie coal attemperatures ranging from 13002-4000 C.. and it has also that veryfinely pulverized iron ore can he reduced in the presence of carbon atabout the same temperature. Therefore, by treating coal and iron both invery nely pulverized form at about BOO-400 C. via.: the maximum yieldoit oil from the coal, the reduction oi the iron ore particles, and theavoidance oit sintering or agglomerating or slagrging the impurities oneccount oi? the low temperature. The iron particies can be completelyreduced in this man ner and will be 'recovered as metaliic partreatmentof the coal" A still further object of 'the invention severa-lbeneficial results accruef unes mamma with, but @t attached a,

the impurities of the ore o1' the impurities f of the coal. separatedthe material by magnetic means, electrostatic means, Water or oilflotation. When The metallic iron can then be' vthe iron iswanted in theform of pigs, it

canbe melted. with the carbon and collected in a hot hearth, and whenthe iron is Wanted in the `tinal pig form, it is not necessary to j .y

con

completely reduce the iront ore in the low temperature treatment, but itis suiileient I or removed from the balance of to carry the reductiononly to such av point that all of the iron is magnetic. Wlien the rawcoal is mixed with the: iron oreduring the low temperature treatment,the/water which occurs from the hydrogen content of the coa-l,interferes with the complete re-4 duction of the iron. It does notintorfere'f however, in partly reducing the .iron and making itmagnetlc.

driving out the volatile content of sameand y leaving afixed carbon.

The process is particularly applicableto the treatment of fine dust madeby all enf istinti blast furnaces, and it contem lates the mixture ofthe dust with pulverize carbonace'ous material and its treatment as deAscribed above. I

lt is, however, a feature of the proceseV that the iron ore ispulverized `by either wot or dry grinding machinery, and that the coalis likewise pulverized to mix with the ore. The process may be carriedout in different manner` and as one illustration, after pulverization ofthe coal, if pulverized wet, dehydration istresorted to and the two ized(particles and impurities will then ybe intro need to a mixer with adefinite quantity is subjected' to the action cf fuel oil in the ratiocib-approximately one part of -oil to two parte of carbon by weight,,which re'- sults in the formation 'of an amalgam vor" 4substantiallypure-carbon and oil, free from the other substances. The oil is'ldelivered ioo of water and after which the mixture The low temperato ry,g Y reparos the iEueLliowjV ever, for the nal re ucton of the iron byyto the material suspended in the Water from anyy suitable source. Thispurilication of the carbonaceous material is carried von in a `'mannerdescribed in my Patent No.

'1420163, granted June 20, 1922, in which thev amalgam, after beingformed, is subjected to distillation so as vto obtain the carbonvarti'cles'free of the oilvused to effect its pur' cation. i l l Fromthe separator'the ore is again conveyed t a mixer and there commjngledwith the purified and carbonized coal particles, and the mixtureis'iiitroduced to a combustion tube haviiig a' reducing atmosphere inwhich the reduction'of the iron particles is1 ignates a lcoal. receiverhaving a source of' communication with the dry pulverizer B, and

the Wet pulverizerl B. Afrepresents an ore receptaclefor iron Aore lorthe like, communicatingivith either the Wet vCrusher B3 or the` dryCrusher B2. The material from the receivers A and A may be-introduced toeither a dry or Wet pulverizer to undergo pulveri'zation, a` Wetpulverizing having the f advantage of being cheaper in operation,

but dehydration must necessarily folloiviwet crushing, While drycrushing can only be` done at a high cost, although it offers theadvantage of eliminating 'the step of dehydration. If coal'i'spulverized Wet, it is introduced to the dehydrator C', beforedelivery the coal, which-is preferably suiiiciently fine` to physicallyseparate the lparticles of im `puritiesfrom the carbonaceous content ofto the mixer D, but if dry ground, is led directly'from the pulverizerto the"A mixer l). Various types of apparatus maybe employed fordehydrating the material, and -niay consist of mere thickening tanks sothat the materials'may be settled and the water removed therefrom,,carrying such impurities as soluble salts. After a vreduction of thecoal, and a similar reduction of theii'on ore to detach the impurities,a charge of coal is introducedl to the mixer D with a charge of iron orewith its detachedimpuri-- ties itbeing understood that yif the coal ispulvei'ized wet, vit is delivered rst lto the delrvdrator C and then tothe mixerl D. The

. entireamoun't of coalnecessaryto 'reduce the iron-play be"`introducedto this mixer Withthe'iifore,.while only" a slight portieri ofthecoah'suilicientfto partly reduce the iron, may

be conveyed to the; miner., Assuming, hoW-.

ever, that the entire charge is introduced to the mixer, the samesiscommingled therein, and conveyed to the loW temperature treat-- nientchamber E, adjacent theinixer. This chamber is provided with ya centralretort heated by indirect heating, resulting' from,

the-burning of a fuel such as combustible gases, or the like, which mayor may not be the volatile substances removed from" the coal. Thepassage of the material through the retort causes a distillation of thecoal,

removing volatile-v lgases and' lay-products therefrom, While the ironor like ore-is partially reduced. Of course thc entire charge of ore maybe induced, but the temperature of the retort is preferably maintainedsuffi. cientlylow, say from'BOO to 400 degrees centigrade to effect a-maximum recovery of the foil from coal,- and at the .saine time preventa lcomplete reduction or siagging or sintering the metal.- The heattreatment is sufli-- cient to carry the reduction only'to such a pointas to rendei iron magnetic and to ent able'a Iseparation tobe latereffected. The distilled gases: from the Iretort E, escape through thepipe Ef to the, combustion chamber N, to be later described, While theheavier volatile products-of the coal pass to the condenser F where theyundergo condensation, and the recovered oils are delivered through afeeding conduit F to an amalga pear. The earbonized particles and thepar- ,tially reduced ore lfrom the retort E pass onto' the separator'GWhich may be of any convenienhtype, ybut-.is preferably a magneticseparator if the `ore undergoing treat- 'nienty is an iron o're. In thisseparatorthe "mator J, for purposes which will later ap.` f

partially reduced iron Whichlias been rendered capable of separation byreason of the heat treatment, is' removedfrom the carbonized'dust Withany impurities-Which eX# ist, and conveyed bythe pipe Glto a suitablemixer I,",connnunicating with the amalgamator J.4 Water is added to thismixture with oils coming from the condenser F, or from an outsidesource, and the entire mass agitated to form an amalgam, excluding therimpurities from the carbonaceous mattei", in

the'mannei disclosed in my copending application hereinabove iientioned.The iron from the magnetic sepbrator G passes to a mixer l-l. Thisinixeris in communication Witlia low temperature retort K, receiving theamalgam lof coal and oil from -the amalgamator J, which amalgamatedsubstances areV distilled by the heat in the retort, and the carbonized`particles intro- 'duced by the feed pipeK to the mixer H.

From this mixer substantially pure carbon dust and partially reducediron ore are Aconveyed ,to the combustion tube N, having a reducingflame therein, resulting in the combustion of the pure carbon, with theproper manipulation of air serving to comintroducedto the combust u thehot collecting hearth @i receiving; the.'

y bustion tube N is in proper definite ratios-,1

. features oi': which consists in the reducing of 1 l! l carbon treed ciits deleterin :cendrier piet-ely reduce the ore introduced to tno tort.lurified carbon purticlee h voy vde;- cided advantage `over raw cool intno ro Tuo tion of iron in view ci when.

4raw cool is mired with iron ore during 'ii lov.'

iiicli oc curs from the hydrogen ofi the ,cool interferes with thecomplete reduction o'the iron, and it has likewise been found tiret hydrocarbons serionely. with the complete reductie oil iron ores to moltennietah which Aobiobtienefere not 'enteinpereture treatnieiit the-waiter`countered when using-pore cnrbonz,v Carbon monoxide fgenoroted in thelow temperature oi the,y tort' muy lbe molten iron und any carboninononide gases. The reduced iron conveyed the hearth O through odisciiergge pipe fior any further and subsequent treo. nent may benecessary. Tit will be undisirstood thotunfhen 'iron is Wanted in theiorn'r ci pigs, recon be melted with the carbon end collected on thehearth. 'The mixture off purilied iron and carbon that is introduced. tothe cointhe salient various ores by ous impurities. This here been'loundto en eble the production of o,y :iuperior product in minore limitedtiineithen is possible when using ruw cool or en colte 'for reducingviron. wl

llt 'is e( dent that corrib'oetible grises@ pro-` duced.y this processgeither 'the low temper-zitiere retorts und lil, or thecoinbu'stiomrediicing clitiinber hl, and hot hearth 0f, cenfbe'titel-tl..l for purposes than producing; the nece emfyiicet in thevarious treatment @bombe euch igor instance es for sale esmunicipalor"`iriclustriol gee if this is found more profitable.llorbonized, dust i those produ or other fuels con be successfullyYemployed in.the"louiteinperetiire retorte lil and' li,

tvliile purified carbon iiiziy be employed iii' lt should be recog-'coriibnstion tube ni'xed that the coinbue e produced in the lowteijnperet cretoruu d in es well.

,d in the duiniber tl :ire

in the lo f v ornied while e combustion due to the indirect .heettreaton tube li, or to nt menne gior inont and sire therefore notdiluted, while the vgases generated iii-the hot collecting hearth @Earise from e closely regulated ratio oi nir end cerbon dust. i

instead of mining the entire quantity' of pulverized cool with thepulverized iron ore in the iniier il, e relatively smell quenn tity of'the coal moy be introduced to this niiirture, suliicient only to causea partiel y reduction of the'iron in the low temperature retort E,While. the remaining lpulverizcd coal will be directly introduced`through u suitable pipe' to the n'iizier l to undergo a .treatmentinthe ainiilgainutor J, and then subjected to e heat treatment in thelon7 tenilpeinture retort Reporter which the heavy oils, light oils,ammonio., and .thc like, :ire

collected by the condenser `lid and certain of these products introducedto the hot 'collecta ing hearth O) for carrying` on o reduction oi' themetal, While all or other or' the prod uct-s may be collected for otheruses as mayl be found more profitable, if the process .is

carried on in this manner, then the small 1 quantity of coal introducedto the retort E is separated from the partially reduced iron by themagnetic separator G, and this coal wif-ith its carbonaceous dustconveyed to the mixer l, and the gases reinoyed therefrom, collected inthe manner hereinbeifore described.

Having thus. described the invention7 what l claim is:

l. The process oi' treatingf orcs7 which comprises mixing finelycoiiiiriinuted' ore por ticle-s 'with finely divided cnrbonuccous fuel*porticieesubstantially 'freed of hydrocarbon, and 1n then burning thefuel particles inixed lwith the ore in e reducing atmosphere to yreducethe ore.

9h The procese of treating ores, Which comprises mixing iinelycornniinuted ore with fine particles of coal, in subjecting the mixedmaterials tothe presence of heat to ,remove the voletiles'froni the cooland to render the ore susceptible of separation from its impurities, inseparating the ore from its, impurities, and in then mixingthe seinewith the coiniiiinuted corbonaceous ii'iateriul visubsfnifitisilly 'freeof hydrocarbons, ond in burning the carbonaceous "fuel inthe presence ofthe ore to ,reduce i'lhe saine.

y 3. The process of treating iron ore intermixed with pulverized coul,which comprises preliminar-ily heating the ii'itciinixed mate"-riiile-to partially reduce the ore ond reinove the volatiles from 'thecool, in eil'ecting e,

'separation of `the iron particles of the ore :from impurities, in.removing the car -bonized particles the cool from non-carbonoceousmotregond in then burning the cerbonized peri les in the presence of thelpartiallyred-deed ore to completely reduce 'the ore to meti/ile.

4 The processof treating iron ore., which comprises mixing the ore in acomminuted condition With finely pulver-ized carbonaccous 't'uel freedc't' its hydrocarbon, and in .burning the tine fuel inthe presenceoiip'they atmosphere to reduce iburned in aA reducing atmosphere toreduce the ore.

65 The process of treating iron ore inter-- mixed with pulverized coal`which consists in subjecting the mixed substances to a heat treatment toremove the volatiles from the coal and place the ore in a condition topermit a subsequent separation of the ore from its impurities, inseparating the ore from impurities and the carbon )articles of the coalfrom gangue, andin tlien mixing .the purilied carbonized particles withthe partially reduced ore vto be burned in the presence of the ore in areducing atmosphere to completely reduce the orc.

7. The process ot' treating iron ore mixed with pulvcrized coal, whichconsists in subjecting the mixed comminuted substances to an indirect'heat treatment; to partially rcduce the orc and remove volatiles'fromthe comminutcd coal, in eiceting a separation ot' the ore fromimpurities, and the cari bonized particles ot the coal from non-can-bonaceous matter, and in then reducing the orc by mixing the same withthe puricd carbonized particles to be burned 'in the presenceoi the orein a reducing atmosplicre.

8. The process et treating iron ore mixed with puli'erized coal toreduce the same, which consist"` in subjecting the mixed sub-v stancesto a heat treatment to remove the volatiles from the coal and topartially rcducc the ore in' effecting a magnetic separationo the orctrom impiuitics, in collecting the carbonizcd particles andnon-carbonaceous matter ot' the coal, in applying an agent to saidsulxstances to separate the carbonized particles from impurities, and inthen utilizing` the carbonized particles for a fuel to be burned in thepresence of the purified atmosphere to reduce the ore.

The process of treating ores, which consists in finely comminuting anore, in comminuting coal to a tine state otl division,'in intermixingthe comminujted materials, in 'subjecting the aggregate to a heattreatment to partially reduce the ore and to remove the volatiles fromthe coal, in separating the ore from its impurities,-and in removingcarbon' sufficient temperature to remove volatiles from the coal lbut ata temperature too loW to cause slagging or sintering of the ore," ineifecting a separation of the ore from its impurities, and in thenmixing thev partially treated ore with a carbonaceous fuel to be burnedin the presence of the ore to com-4 plete its reduction to molten,metal.

l1. The process of'treating iron ore intermixed with coinminuted coal,which comprises subjecting the mixed substances 'to a heat treatment ofrelatively. low temperature sufiicient to distill the v'olatile productsfrom the Acoal and to partially reduce the ore without slaggingthe same,in separating the ore 'from impurities, and removing the carbonizedparticles from non-carbonaceous matter, and in then smelting thepartially reduced ore with the carbonized particles 12. The process oftreatingl ores in a fine state of division associated with pulverizedfuel containing carbon substantially free ot hydrocarbon, whichcomprises burning the fuel inthe presence of the ore to reduce the oretol molten metal.

13. Theprocess of treating finely pulverized ores mixed 'with finelydivided carbonaceous material, Which consistsin subjecting the aggregateto a low temperature heat Atreatment sufficient to distill the Volatileproducts from ,the carbonaceous material without slaggng or sinteringthe ore in separating the ore from impurities, and in then reducing theore' to metal by 'burning the treated carbonaceous 'fuel free ofhydrocarbons in the presence of the ore.

14. The process of treating ore mixed with a" carbonaceous fuel, whichconsists 1n subjecting the aggregate When in such a line.

state of division as to detach impurities from the fuelI and ore to aheat treatment suiiicient to distill volatile products from the.coalwithout slagging or sintering the ore, in effecting a separation of theore from its impurities, in removing carbonized particles fromnon-carbonaceous matter, and in then burning the carbonized particles inthe iis presence of the ore to completely reduce the 1ore to` moltenmetal.

15. The process ofitreating ore mixed With carbonaceo'us fuel, whichconsists in subjecting the mixed ore and fuel Whenin such a linecomminuted form as to detach impurities from the ore and thecarbonaceous content of the fuel to a heat treatment of such a ore, inseparating the ore from temperature as to remove volatiles from thecarbonaceous matter, but of n temperature too low to cause slagging orsintering of the ore, in separating; impurities from the ore, inremoving carbonized particles from noncombustible matter, and in finallyburningV the carbonized particles in the presence of the ore tokeffects, complete reduction of the ore to molten metal.'v

' 16. Theprocess of treating ores, comprises subjecting finelypulverized ore to a heat treatment to partially reduce the itsimpurities 'and in then mixing` the ore with a inely conuninuteclcurbonaceous material to be burned in the presence tliereo1 to' reducethe same to metal.

17. The process ofV treating ores, which consistsv in subjecting finelycomminuted ores to a low temperature' heat treatment,

suieient to partially reduce the ore Without which' slagging the sume,from its impurities after such partial reoiuc- Lion, and in thenmixingtlie ore with e finely divided carrlaonueeous fuel substantiallyfree ci: hyclrocerbon to ne burned in the presence ol" the ore tocomplete the reduction thereof.

The process of reducing ores., which comprises mixing' finely dividedcarboneccous particles and ore, in subjecting; tlie mixed substances tozi heat treatment. to re move volatiles from. the earooneoeous particlesand to partially reduce the ore, in separating the ore from itsimpurities, :incl in then mixing the ore with the carboni/.ed particlessubstantially freed o'l' their hydrocarbons, which pertieles are burnedin the presence of the ore to eemplete the reduction thereof.

ln testimon' whereof zillix my signature.

ALTER EDl/Vll TRENT.

in separating the ore imu

